Retry delayed SPT retrieval in MPP pay

.changeset/spt-retrieval-backoff.md

@@ -0,0 +1,5 @@
+---
+'@stripe/link-cli': patch
+---
+
+Retry delayed shared payment token retrieval in both interactive and continued MPP payment flows.

packages/cli/src/commands/mpp/pay.test.ts

@@ -57,6 +57,7 @@ beforeEach(() => {
 });
 
 afterEach(() => {
+  vi.useRealTimers();
   vi.unstubAllGlobals();
 });
 
@@ -395,6 +396,47 @@ describe('payWithSpt', () => {
     expect(refreshedResponse.bodyUsed).toBe(true);
   });
 
+  it('waits for SPT propagation when continuing an approved spend request', async () => {
+    vi.useFakeTimers();
+    vi.setSystemTime(0);
+    const retrievedAt: number[] = [];
+    const repository = {
+      retrieve: vi.fn().mockImplementation(async () => {
+        retrievedAt.push(Date.now());
+        return {
+          id: 'lsrq_123',
+          status: 'approved',
+          credential_type: 'shared_payment_token',
+          ...(retrievedAt.length === 8
+            ? { shared_payment_token: { id: 'spt_test_123' } }
+            : {}),
+        };
+      }),
+    } as unknown as ISpendRequestResource;
+    const fetcher = vi
+      .fn()
+      .mockResolvedValueOnce(challengeResponse())
+      .mockResolvedValueOnce(new Response('paid'));
+    vi.stubGlobal('fetch', fetcher);
+
+    const resultPromise = runMppPayWithSpendRequest(
+      'https://merchant.example/challenge',
+      'lsrq_123',
+      'GET',
+      undefined,
+      undefined,
+      repository,
+    );
+    await vi.runAllTimersAsync();
+
+    await expect(resultPromise).resolves.toMatchObject({
+      status: 200,
+      body: 'paid',
+    });
+    expect(retrievedAt).toEqual([0, 1000, 2000, 3000, 5000, 7000, 9000, 11000]);
+    expect(fetcher).toHaveBeenCalledTimes(2);
+  });
+
   it('rejects an explicit amount that conflicts with the challenge', async () => {
     const repository = approvedRepository();
     const fetcher = vi.fn().mockResolvedValueOnce(challengeResponse());

packages/cli/src/commands/mpp/pay.tsx

@@ -104,6 +104,10 @@ export interface MppProbe extends MppRequest {
   response: Response;
 }
 
+const SPT_RETRIEVAL_DELAYS_MS = [
+  0, 1000, 1000, 1000, 2000, 2000, 2000, 2000,
+] as const;
+
 export async function probeMppRequest(
   initial: MppRequest,
   fetcher: typeof fetch = fetch,
@@ -164,7 +168,7 @@ export async function runMppPayWithSpendRequest(
   repository: ISpendRequestResource,
   approvedChallengeHeader?: string,
 ): Promise<PayResult> {
-  const spendRequest = await repository.retrieve(spendRequestId, {
+  let spendRequest = await repository.retrieve(spendRequestId, {
     include: ['shared_payment_token'],
   });
 
@@ -182,8 +186,19 @@ export async function runMppPayWithSpendRequest(
       `Spend request must be approved (current status: ${spendRequest.status})`,
     );
   }
+  for (const delayMs of SPT_RETRIEVAL_DELAYS_MS.slice(1)) {
+    if (spendRequest.shared_payment_token) break;
+    await new Promise((resolve) => setTimeout(resolve, delayMs));
+    const retrieved = await repository.retrieve(spendRequestId, {
+      include: ['shared_payment_token'],
+    });
+    if (!retrieved) {
+      throw new Error(`Spend request ${spendRequestId} not found`);
+    }
+    spendRequest = retrieved;
+  }
   if (!spendRequest.shared_payment_token) {
-    throw new Error('Spend request does not have a shared payment token');
+    throw new Error('Failed to retrieve shared payment token');
   }
 
   return payWithSpt(
@@ -402,14 +417,15 @@ export async function runMppPayFullFlow(
 
   // 6. Retrieve with SPT (retry briefly in case of propagation delay)
   onStep?.('signing');
-  let withSpt = await repository.retrieve(spendRequest.id, {
-    include: ['shared_payment_token'],
-  });
-  for (let i = 0; i < 3 && withSpt && !withSpt.shared_payment_token; i++) {
-    await new Promise((r) => setTimeout(r, 1000));
+  let withSpt = null;
+  for (const delayMs of SPT_RETRIEVAL_DELAYS_MS) {
+    if (delayMs > 0) {
+      await new Promise((resolve) => setTimeout(resolve, delayMs));
+    }
     withSpt = await repository.retrieve(spendRequest.id, {
       include: ['shared_payment_token'],
     });
+    if (withSpt?.shared_payment_token) break;
   }
   if (!withSpt?.shared_payment_token) {
     throw new Error('Failed to retrieve shared payment token');